csky: Optimize arch_sync_dma_for_cpu/device with dma_inv_range

DMA_FROM_DEVICE only need to read dma data of memory into CPU cache,
so there is no need to clear cache before. Also clear + inv for
DMA_FROM_DEVICE won't cause problem, because the memory range for dma
won't be touched by software during dma working.

Changes for V2:
 - Remove clr cache and ignore the DMA_TO_DEVICE in _for_cpu.
 - Change inv to wbinv cache with DMA_FROM_DEVICE in _for_device.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

1 files changed, 10 insertions, 1 deletions

diff --git a/arch/csky/mm/cachev2.c b/arch/csky/mm/cachev2.c
index baaf05d69f44..b61be6518e21 100644
--- a/arch/csky/mm/cachev2.c
+++ b/arch/csky/mm/cachev2.c
@@ -69,11 +69,20 @@ void dma_wbinv_range(unsigned long start, unsigned long end)
 	sync_is();
 }
 
+void dma_inv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.iva %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
 void dma_wb_range(unsigned long start, unsigned long end)
 {
 	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
 
 	for (; i < end; i += L1_CACHE_BYTES)
-		asm volatile("dcache.civa %0\n"::"r"(i):"memory");
+		asm volatile("dcache.cva %0\n"::"r"(i):"memory");
 	sync_is();
 }